Pons, Liz and Délia, Marie-Line
and Basséguy, Régine
and Bergel, Alain
Effect of the semi-conductive properties of the passive layer on the current provided by stainless steel microbial cathodes.
(2011)
Electrochimica Acta, 56 (6). 2682-2688. ISSN 0013-4686
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(Document in English)
PDF (Author's version) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader 310kB |
Official URL: http://dx.doi.org/10.1016/J.ELECTACTA.2010.12.039
Abstract
Geobacter sulfur reducens biofilms were formed under constant polarisation at −0.6 V vs. Ag/AgCl on stainless steel cathodes to catalyse the reduction of fumarate. The time-evolution of the current strongly depended on the quality of the inoculum. Inoculating with young cells significantly shortened the initial lag-phase and using the same inoculum improved the reproducibility of the current–time curves. The whole set of experiments showed that 254SMO stainless steel provided higher current densities (on average 14.1 A/m2) than biofilms formed on 316L stainless steel (on average 4.5 A/m2). Biofilm coverage assessed by epifluorescent microscopy showed that coverage ratios were generally higher for 316L than for 254SMO. It must be concluded that 254SMO is more efficient in transferring electrons to bacterial cells than 316L. Mott–Schottky diagrams recorded on both materials under conditions of electrolysis in the absence of microorganisms showed that the surface oxide layers had similar n-type semi-conductive behaviour for potential values higher than the flat band potential. In contrast, 316L exhibited slight p-type behaviour at potential lower than the flat band potential, while 254SMO did not. The higher electrochemical performances of biocathodes formed on 254SMO are explained by semi-conductive properties of its passive layer, which prevented the p-type behaviour occurring in cathodic electrolysis conditions.
Item Type: | Article |
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Additional Information: | Thanks to Elsevier editor. The definitive version is available at http://www.sciencedirect.com The original PDF of the article can be found at : http://www.sciencedirect.com/science/article/pii/S0013468610016725 |
HAL Id: | hal-03539299 |
Audience (journal): | International peer-reviewed journal |
Uncontrolled Keywords: | |
Institution: | French research institutions > Centre National de la Recherche Scientifique - CNRS (FRANCE) Université de Toulouse > Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE) Université de Toulouse > Université Toulouse III - Paul Sabatier - UT3 (FRANCE) |
Laboratory name: | Laboratoire de Génie Chimique - LGC (Toulouse, France) - Bioprocédés et systèmes microbiens (BioSyM) |
Statistics: | download |
Deposited On: | 29 Jun 2012 09:17 |
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